[KPI-02] Setup Performance Monitoring

[kilip]

Description

Configure performance monitoring to ensure first page load time stays under 2 seconds on standard mobile 4G.

Subtasks

• KPI-02-ST-01 Enable Vercel Analytics
• KPI-02-ST-02 Configure Core Web Vitals monitoring
• KPI-02-ST-03 Set up alerts for performance regression

Acceptance Criteria

• KPI-02-AC-01 First page load < 2 seconds on 4G (measured via Vercel Analytics)
• KPI-02-AC-02 Core Web Vitals tracked per page

Technical Notes

• Docs: PRD#21-success-metrics-kpis · TDD#2-tech-stack